From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-13.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C57B7C433DB for ; Tue, 19 Jan 2021 18:43:42 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 8526122E00 for ; Tue, 19 Jan 2021 18:43:42 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8526122E00 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:42604 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1l1vyf-0006vl-Jd for qemu-devel@archiver.kernel.org; Tue, 19 Jan 2021 13:43:41 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:44128) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1l1vRT-0004eZ-4t for qemu-devel@nongnu.org; Tue, 19 Jan 2021 13:09:23 -0500 Received: from us-smtp-delivery-124.mimecast.com ([63.128.21.124]:26293) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1l1vRN-0006ET-Kq for qemu-devel@nongnu.org; Tue, 19 Jan 2021 13:09:22 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1611079756; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=2tbpkY0vt/J1aDs2tPVQJBEXeaNX78dFf03kwzy2h+o=; b=afd9zwqjmYa0EVECpIa7uCpuSKV+Zy/NRwvJSG7Y01k0PIgGR22D2UF8xfQU4eWtsLoQTu GlEbgatL4K0SFsRHOT4wDdIu/JIIsRMel/Pe94+c+lN/zyF5LXShJFoD9InY+nQ8G4rWFI kDdwNaLsm1P+pMI+w4NhVkFlJ07s7VY= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-288-JnHFZADoNl6DZfBlTfNoAw-1; Tue, 19 Jan 2021 13:09:13 -0500 X-MC-Unique: JnHFZADoNl6DZfBlTfNoAw-1 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id A268910054FF; Tue, 19 Jan 2021 18:09:12 +0000 (UTC) Received: from merkur.fritz.box (ovpn-115-149.ams2.redhat.com [10.36.115.149]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 36FDF19C84; Tue, 19 Jan 2021 18:09:10 +0000 (UTC) Date: Tue, 19 Jan 2021 19:09:09 +0100 From: Kevin Wolf To: Vladimir Sementsov-Ogievskiy Subject: Re: [PATCH v2 12/36] block: refactor bdrv_child* permission functions Message-ID: <20210119180909.GK5012@merkur.fritz.box> References: <20201127144522.29991-1-vsementsov@virtuozzo.com> <20201127144522.29991-13-vsementsov@virtuozzo.com> MIME-Version: 1.0 In-Reply-To: <20201127144522.29991-13-vsementsov@virtuozzo.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=kwolf@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Received-SPF: pass client-ip=63.128.21.124; envelope-from=kwolf@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -29 X-Spam_score: -3.0 X-Spam_bar: --- X-Spam_report: (-3.0 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.195, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: qemu-block@nongnu.org, armbru@redhat.com, qemu-devel@nongnu.org, mreitz@redhat.com, den@openvz.org, jsnow@redhat.com Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Am 27.11.2020 um 15:44 hat Vladimir Sementsov-Ogievskiy geschrieben: > Split out non-recursive parts, and refactor as block graph transaction > action. > > Signed-off-by: Vladimir Sementsov-Ogievskiy > --- > block.c | 79 ++++++++++++++++++++++++++++++++++++++++++--------------- > 1 file changed, 59 insertions(+), 20 deletions(-) > > diff --git a/block.c b/block.c > index a756f3e8ad..7267b4a3e9 100644 > --- a/block.c > +++ b/block.c > @@ -48,6 +48,7 @@ > #include "qemu/timer.h" > #include "qemu/cutils.h" > #include "qemu/id.h" > +#include "qemu/transactions.h" > #include "block/coroutines.h" > > #ifdef CONFIG_BSD > @@ -2033,6 +2034,61 @@ static void bdrv_child_perm(BlockDriverState *bs, BlockDriverState *child_bs, > } > } > > +static void bdrv_child_set_perm_commit(void *opaque) > +{ > + BdrvChild *c = opaque; > + > + c->has_backup_perm = false; > +} > + > +static void bdrv_child_set_perm_abort(void *opaque) > +{ > + BdrvChild *c = opaque; > + /* > + * We may have child->has_backup_perm unset at this point, as in case of > + * _check_ stage of permission update failure we may _check_ not the whole > + * subtree. Still, _abort_ is called on the whole subtree anyway. > + */ > + if (c->has_backup_perm) { > + c->perm = c->backup_perm; > + c->shared_perm = c->backup_shared_perm; > + c->has_backup_perm = false; > + } > +} > + > +static TransactionActionDrv bdrv_child_set_pem_drv = { > + .abort = bdrv_child_set_perm_abort, > + .commit = bdrv_child_set_perm_commit, > +}; > + > +/* > + * With tran=NULL needs to be followed by direct call to either > + * bdrv_child_set_perm_commit() or bdrv_child_set_perm_abort(). > + * > + * With non-NUll tran needs to be followed by tran_abort() or tran_commit() s/NUll/NULL/ > + * instead. > + */ > +static void bdrv_child_set_perm_safe(BdrvChild *c, uint64_t perm, > + uint64_t shared, GSList **tran) > +{ > + if (!c->has_backup_perm) { > + c->has_backup_perm = true; > + c->backup_perm = c->perm; > + c->backup_shared_perm = c->shared_perm; > + } This is the obvious refactoring at this point, and it's fine as such. However, when you start to actually use tran (and in new places), it means that I have to check that we can never end up here recursively with a different tran. It would probably be much cleaner if the next patch moved the backup state into the opaque struct for BdrvAction. Kevin